If you don't mind the usually small cost of copying,

my @array_2 = grep { my $element = $_;
                     $element->func() eq 'TEST'
                   } @array_1;
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It's basically the same as my ($arg1, $arg2) = @_; in subs.

If you're dealing with very long strings and want to avoid the cost of copying without having to deal with references, you can create an alias,

my @array_2 = grep { our $element; local *element = \$_;
                     $element->func() eq 'TEST'
                   } @array_1;
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or

use Data::Alias qw( alias );
my @array_2 = grep { alias my $element = $_;
                     $element->func() eq 'TEST'
                   } @array_1;
[download]